Method for dewatering an operating substance, dewatering device and operating-substance supply device

ABSTRACT

A method for dewatering an operating substance, more particularly a fuel, preferably during the operation of a vehicle, more particularly a rail vehicle, includes conveying an operating substance from an operating substance tank. Water present on or in the fuel is first collected in a water container, and water is conveyed, in chronological order, from the water container back to the operating substance tank, then to an exhaust system and/or from the operating substance tank to the exhaust gas system. A dewatering device for an operating substance, more particularly a fuel for a vehicle, more particularly a rail vehicle, includes a water container, in which water present on or in the fuel is collected. The dewatering device has a dewatering conduit or line which runs from the water container to an operating-substance tank of the vehicle and/or to an exhaust-gas system of the vehicle.

The invention relates to a method for dewatering an operating substance,in particular a fuel, preferably during operation of a vehicle, inparticular a rail vehicle. Furthermore, the invention relates to adewatering device for an operating substance, in particular a fuel, andto an operating substance supply device, in particular a fuel supplydevice, for a vehicle, in particular a rail vehicle. Furthermore, theinvention relates to an engine, in particular a diesel engine, a drive,in particular a diesel drive, a power unit or a vehicle.

In the case of a rail vehicle, in particular a diesel locomotive(traction unit), the problem exists that an excessive amount of watercan be situated in an operating substance, in particular a fuel. Anintroduction of water into the operating substance takes place, forexample, via tank depots, a defective tank closure, condensation water,etc., an excessive amount of water inevitably leading to damage, inparticular engine damage. Furthermore, the fuel is removed from a fueltank at the bottom with the aim of minimizing silting up. Here, however,water which has settled in the fuel tank is also conveyed into a filterand in the direction of an internal combustion engine of the railvehicle.

In order to achieve damage and therefore an operational extension of arail vehicle despite operating substance which is contaminated withwater, it is necessary to remove the water from the operating substance.This applies, in particular, to an operational extension and anavoidance of engine damage in the case of a diesel locomotive, thediesel fuel of which is contaminated with water. A conventional solutionof said problem consists in that the water which is entrained in thediesel fuel is separated in a separate water container. A traction unitdriver is given the prompt to discharge the water above a fixed fillingquantity of water in the water container. This is usually ignored and asa consequence leads to damage in an internal combustion engine of thediesel locomotive.

It is an object of the invention to specify an improved method fordewatering an operating substance, in particular a fuel, preferablyduring operation, for example, of a vehicle, in particular a railvehicle. Furthermore, it is an object of the invention to specify acorresponding dewatering device for the operating substance, and acorresponding operating substance supply device for an engine, forexample, of a vehicle, in particular of a rail vehicle. In accordancewith the invention, undesired conveying of water to an engine or to theengine is to be avoided, in order to prevent damage in the engine of thevehicle.

The object of the invention is achieved by way of a method fordewatering an operating substance, in particular a fuel, preferablyduring operation of a vehicle, in particular a rail vehicle; by means ofa dewatering device for an operating substance, in particular a fuel ofa vehicle, in particular of a rail vehicle; by means of an operatingsubstance supply device, in particular a fuel supply device for avehicle, in particular a rail vehicle; and by means of an engine, inparticular a diesel engine, a drive, in particular a diesel drive, apower unit or a vehicle; as claimed in the independent claims.Advantageous developments, additional features and/or advantages of theinvention result from the dependent patent claims and/or the followingdescription of the invention.

In the case of the dewatering method according to the invention,operating substance is conveyed out of an operating substance tank,preferably of the vehicle, and water which is present on/in theoperating substance is in the process first of all separated into awater container, water being conveyed, in chronological order, out ofthe water container (back) into the operating substance tank, (further)into an exhaust gas system, preferably of the vehicle, and/or out of theoperating substance tank (again) to the exhaust gas system. In the firstcase, this is a method for water recirculation and, in the second case,this is a method for water removal. A combination is a method for waterremoval with water recirculation or possibly with water recirculation.

Here, the water is preferably present at least in droplet form on/in theoperating substance. A water container is to be understood to mean apartially closed space (vessel) which is suitable for collecting adefined quantity of water. Here, the water container does not need to bedesigned specifically as a water container; a space for collecting wateris sufficient. The water container can thus, for example, also be asection of an operating substance filter, such as of an operatingsubstance prefilter. It is of course also possible to design the watercontainer specifically as a water container of this type. In the case ofthe operating substance filter, this can be a hollow region of a housingof the operating substance filter, in which hollow region, for example,there is no filter material.

In accordance with the invention, in the case of a sufficiently filledor substantially filled water container, water can be conveyed out ofthe water container back to/into the operating substance tank again.Furthermore, a liquid (water and/or operating substance) in the watercontainer can be conveyed temporarily or permanently back to/into theoperating substance tank again. Moreover, in the case of a sufficientlyfilled or substantially filled water container and an at leastsufficient exhaust gas volumetric flow, water can be conveyed out of thewater container to/into the exhaust gas system. Furthermore, in the caseof an at least sufficient exhaust gas volumetric flow, water can beconveyed out of the operating substance tank and/or out of the watercontainer to/into the exhaust gas system.

In one embodiment, water can be conveyed by means of a water conveyingdevice substantially at the bottom into the operating substance tank.That is to say, liquid water is added to a liquid (operating substance,preferably water) substantially at the bottom in the operating substancetank. Furthermore, in one embodiment, water can be conveyed by means ofa water conveying device into the exhaust gas system. That is to say,liquid water is added to a hot exhaust gas flow, preferably in anexhaust gas silencer of the exhaust gas system, preferably evaporatessubstantially there and is discharged into the surrounding area. Here, adewatering device or an opening of the dewatering device on/in theexhaust gas system can possibly additionally be configured as a vacuumpump.

Furthermore, in one embodiment, water can be conveyed by means of awater conveying device into the operating substance tank and/or watercan be conveyed by means of said water conveying device into the exhaustgas system. That is to say, this is a combination of the above twoexemplary embodiments. The water conveying device is configured, inparticular, as a dewatering pump. In one embodiment, water can becapable of being discharged and/or can be discharged out of theoperating substance tank, the water container, a dewatering line and/ora water conveying device. Furthermore, in one embodiment, operatingsubstance can be conveyed out of the operating substance tanksubstantially at the height of a level of the operating substance in theoperating substance tank. This preferably takes place by means of anoperating substance intake float and preferably by means of a preferablyflexible operating substance hose on the operating substance intakefloat.

In one embodiment of the invention, water which is present on/in anoperating substance supply device of an engine can be capable of beingdischarged and/or can be discharged temporally before filling orstarting up of an engine. This can take place, for example, at a waterremoval point of the operating substance tank, of the water container,of the dewatering line and/or of the water conveying device. Inaccordance with the invention, the operating substance can be conveyedtoward an internal combustion engine, and/or water can be conveyed outof the water container by means of the water conveying device, inparticular a dewatering pump. Furthermore, in one embodiment of theinvention, the water conveying device can operate in a manner which iscontrolled by sensor signal, is temporary, is time-controlled in anadjustable manner, or permanently.

The dewatering device according to the invention has a water container,in which water which is present on/in an operating substance can beseparated, the dewatering device having a dewatering line which leadsfrom the water container to an operating substance tank preferably ofthe vehicle and/or to an exhaust gas system, preferably of the vehicle.That is to say, by means of the dewatering line, the water which can becollected in the water container can be conveyed (back) to/into theoperating substance tank, out of the operating substance tank to/intothe exhaust gas system, (furthermore) to/into the exhaust gas system,and/or first of all to/into the operating substance tank and, inchronological sequence, to/into the exhaust gas system.

The dewatering line can have a feed line to a water conveying device anda return line from the water conveying device to the operating substancetank. Furthermore, the dewatering line can have a feed line to a waterconveying device and a forward feed line from the water conveying deviceto the exhaust gas system. Furthermore, the dewatering line can have afeed line to a water conveying device and both a return line from thewater conveying device to the operating substance tank and a forwardfeed line from the water conveying device to the exhaust gas system, itbeing possible for the return line to be coupled fluid-mechanically tothe forward feed line.

It is of course possible to provide the water conveying devicesubstantially directly on the water container, on the operatingsubstance tank or on the exhaust gas system. In the case of this type,apart from a relevant connector or relevant connectors, the feed line,the return line and/or the forward feed line, or even the dewateringline itself, are/is dispensed with. The corresponding line is thensubstituted by way of the water conveying device and its connector. Thewater container, the operating substance tank, the dewatering lineand/or the water conveying device can have a water removal point. If thedewatering line has at least one water removal point, this can beprovided on the feed line, the return line and/or the forward feed line.The water removal point can be configured, for example, as a manually orelectromechanically actuable dewatering valve, such as a drain cock.

In accordance with the invention, the operating substance preferablycomes from the operating substance tank. Furthermore, the watercontainer can be part of an operating substance filter of the vehicle,preferably part of an operating substance prefilter of the vehicle.Moreover, the dewatering line and/or the feed line, the return lineand/or the forward feed line can have an actuating means. Furthermore, areturn and/or a forward feed of the water can be capable of beingprevented by means of the actuating means (check valve).

In one embodiment, the dewatering device can be configured in such a waythat operating substance can be conveyed out of the operating substancetank by means of an operating substance intake float which can float onthe operating substance in the operating substance tank and preferablyby means of an operating substance hose which is, in particular,flexible in the operating substance tank. Here, an operating substancesupply device which has the dewatering device is configured in such away that the operating substance can subsequently be conveyed into anoperating substance filter, preferably an operating substance prefilter,and into an internal combustion engine. If an operating substanceprefilter is used, an operating substance main filter is preferablyprovided, furthermore, between the operating substance prefilter and theinternal combustion engine.

The operating substance supply device according to the invention has anoperating substance tank, it being possible for operating substance inthe operating substance tank to be conveyed out of the operatingsubstance tank by means of an operating substance intake float which canfloat on the operating substance in the operating substance tank. Theoperating substance intake float can have a preferably flexibleoperating substance hose, by means of which operating substance can beconveyed out of the operating substance tank. Here, the operatingsubstance hose can be further contact-connected fluid-mechanically, forexample at the top, in the middle or at the bottom in/on the operatingsubstance tank, for which reason the operating substance tank can have acorresponding connector. It is also possible that the operatingsubstance hose is guided through a wall of the operating substance tankand is further contact-connected fluid-mechanically outside theoperating substance tank.

The operating substance supply device can have an operating substanceconveying device downstream of the operating substance intake float orthe operating substance hose. The operating substance conveying device,in particular an operating substance pump, is preferably providedoutside the operating substance tank. Furthermore, the operatingsubstance supply device can have an operating substance filter, inparticular an operating substance prefilter and/or an operatingsubstance main filter, and corresponding operating substance lines.Furthermore, the operating substance tank can have a water removalpoint.

The invention is described in greater detail in the following text usingexemplary embodiments with reference to the appended drawing which isdiagrammatic and not to scale. Sections, elements, components, units,diagrams and/or components which have an identical, univocal oranalogous configuration and/or function are labeled with the samedesignations in the description of the figures (see below), the list ofdesignations, the patent claims and in the figures of the drawing.Furthermore, a possible alternative which is non-exhaustive and/or isnot described in the description (description of the invention (seeabove), description of the figures (see below)) and is not shown in thedrawing, a static and/or kinematic reversal, a combination, etc. withrespect to the exemplary embodiments of the invention and/or acomponent, a diagram, a unit, a structural element, an element or asection thereof, can be gathered from the list of designations.

In the case of the invention, a feature (section, element, structuralelement, unit, component, function, size, etc.) can be of positive (thatis to say, present) or negative (that is to say, absent) configuration,a negative feature not being described explicitly as a feature unless itis noted in accordance with the invention that it is absent. A featureof this specification (description, list of designations, patent claims,drawing) can be used not only in a specified type and/or way, but ratheralso in another type and/or way (isolation, combination, replacement,addition, individual use, omission, etc.). It is possible, inparticular, to replace, add or omit a feature in the patent claimsand/or the description on the basis of a designation and a feature whichis assigned to the latter, or vice versa, in the description, the listof designations, the patent claims and/or the drawing.

Moreover, as a result, a feature can be interpreted and/or specified ingreater detail in a patent claim.

The features of this specification can also be interpreted as optionalfeatures (in view of the prior art which is usually unknown); that is tosay, each feature can be understood to be an optional, arbitrary orpreferred, that is to say not mandatory feature. A separation of afeature, possibly including its periphery, from an exemplary embodimentis thus possible, it then being possible for said feature to betransferred to a generalized concept of the invention. The absence of afeature (negative feature) in an exemplary embodiment shows that thefeature is optional in relation to the invention. Furthermore, in thecase of an identity of the type of a feature, a generic term for thefeature can also be understood (possibly further hierarchical breakdowninto sub-genre, sector, etc.), as a result of which, for example withconsideration of equivalent effect and/or equivalence, a generalizationof one or said feature is possible. In the figures which are merely byway of example:

FIG. 1 shows one embodiment of an operating substance supply deviceaccording to the invention and a first embodiment of a dewatering deviceaccording to the invention for a vehicle,

FIG. 2 shows a second embodiment of the dewatering device according tothe invention for the vehicle, in particular a rail vehicle, and

FIG. 3 shows a third embodiment of the dewatering device according tothe invention for the vehicle, in

The invention is described in greater detail in the following text onthe basis of exemplary embodiments of one embodiment of one variant ofan operating substance supply device 0 (cf. FIG. 1) and of threeembodiments of one variant (cf. FIGS. 1 to 3) of a dewatering device 10for a rail vehicle. The invention is not restricted, however, to avariant of this type and/or the exemplary embodiments which aredescribed in the following text, but rather is of more fundamentalnature, with the result that it can be applied to all dewatering deviceswithin the context of the invention.

A dewatering device according to the invention can thus be applied toall internal combustion engines, in particular diesel engines. Thisrelates, for example, to engines of power generators, trucks, militaryvehicles, rail vehicles, ships, etc. Furthermore, the invention can beapplied to all areas which have to expect contaminated diesel fuels,such as in mining, on construction sites, etc. Relevant manufacturersare, for example, engine manufacturers; engine suppliers, for examplefilter manufacturers; commercial vehicle manufacturers; manufacturers ofpower generators; manufacturers of marine engines, etc.

The drawing shows only those sections which are necessary for anunderstanding of the invention. Although the invention is described andillustrated in greater detail by way of preferred exemplary embodiments,the invention is not restricted by way of the disclosed exemplaryembodiments. Other variations can be derived herefrom without departingfrom the scope of protection of the invention.

FIG. 1 shows the operating substance supply device 0 according to theinvention, preferably configured as a fuel supply device 0, the supplydevice 0 having at least one operating substance tank 20, in particulara fuel tank 20, preferably with an inner protective coating or an innerphosphating treatment. A height 22 or level 22 of an operating substance2, in particular a fuel 2, is marked by way of a triangle 22 in FIG. 1.Air 3 is usually situated above this. The fuel 2 can be removed from thefuel tank 20 by means of a fuel intake float 210 (operating substanceintake float 210) which can float on the fuel 2, and can be conveyedaway from the intake float 210, in particular, through a preferably atleast partially flexible fuel hose 212 (operating substance hose 212).Here, the fuel hose 212 is preferably connected fluid-mechanically tothe intake float 210.

A fluid-mechanical further contact connection of the fuel hose 212 cantake place at a connector which preferably lies on the inside in thefuel tank 20, or the fuel hose 212 is guided to the outside and isfurther contact-connected fluid-mechanically on the fuel tank 20 oranother apparatus, such as a fuel filter 40 (operating substance filter40). Here, the fuel hose 212 can lead to a fuel line 300 (operatingsubstance line 300) which connects the fuel intake float 210fluid-mechanically to the fuel filter 40. Furthermore, the supply device0 can have a fuel conveying device (operating substance conveyingdevice) downstream of the fuel intake float 210, in particulardownstream of the fuel hose 212.

Furthermore, apart from connectors, etc., the supply device 0 cancomprise the fuel filter 40, preferably a fuel prefilter 40 (operatingsubstance prefilter 40) and/or a fuel main filter (operating substancemain filter) and a fuel line 500 (operating substance line 500) from thefuel filter 40 to an internal combustion engine 60, in particular adiesel engine 60, of the rail vehicle. One advantage of said arrangementlies in the fact that the fuel 2 in the fuel tank 20 can be sucked intothe fuel filter 40 via the intake float 210 on a surface or in a surfaceregion of the fuel 2, as a result of which merely a small water quantityis separated in the fuel filter 40 (see below) in comparison with alower intake region (prior art).

In one preferred embodiment of the device according to the invention orthe system according to the invention (drive, in particular dieseldrive, rail vehicle, motor vehicle, etc.), water 1 which is separated ina water container 410 is guided back into a fuel tank 20 (FIG. 1).Furthermore, in one preferred embodiment, water 1 which is separated inthe water container 410 can be conveyed further into an exhaust gassystem 80, where it is evaporated in a flow of a hot exhaust gas 4,preferably in an exhaust gas silencer 80, and water vapor which isproduced is discharged into a local surrounding area (FIG. 2).Furthermore, in one preferred embodiment, water 1 which is separated inthe water container 410 can be guided back into the fuel tank 20 again,and separated water 1 (from the fuel tank 20 or the water container 410)can be conveyed into the exhaust gas system 80 (FIG. 3).

FIGS. 1 to 3 in each case show an embodiment of the dewatering device 10of a fuel 2 (operating substance 2) of the rail vehicle or of its fuelsupply device 0. Here, the dewatering device 10 comprises substantiallya dewatering line 100 which leads from a water container 410 to a fueltank 20 (operating substance tank 20) and/or from the water container410 to an exhaust gas system 80, in particular an exhaust gas silencer80. The dewatering line 100 can have a water removal point 120,optionally with a dewatering actuating means (for example, a dewateringvalve, a drain cock, manually or electromechanically actuable).

For conveying water 1 which is separated in the water container 410, thedewatering device 10 or the dewatering line 100 has a water conveyingdevice 110, in particular a dewatering pump 110. The water container 410can be a part or a section of a fuel filter 40 (operating substancefilter 40), preferably of a fuel prefilter 40 (operating substanceprefilter 40). The water conveying device 110 can have a water removalpoint (not shown), optionally with a dewatering actuating means (forexample, a dewatering valve, a drain cock, manually orelectromechanically actuable). Furthermore, the fuel tank 20 and/or thewater container 410 can have a water removal point 220, 420, optionallyin each case with a dewatering actuating means (for example, adewatering valve, a drain cock, manually or electromechanicallyactuable).

Depending on a position of one or a plurality of actuating means,preferably one or a plurality of electrically actuable and/or manuallyoperable valves, in the dewatering device 10 or the dewatering line 100,water 1 which is separated in the water container 410 can be conveyedback to/into the fuel tank 20 and/or forward to/into the exhaust gassystem 80. Here, furthermore, depending on a position of the relevantactuating means, the fuel tank 20 can be brought into fluid-mechanicalcontact with the exhaust gas system 80. The following embodiments can ofcourse also be applied to an operating substance 2 instead of the fuel2.

In addition to the fuel supply device 0, FIG. 1 shows the firstembodiment of the dewatering device 10. Here, the dewatering line 100comprises a feed line 101 and merely a return line 102. The feed line101 leads from the water container 410 to the water conveying device110/into the return line 102. The return line 102 leads from the feedline 101, from the water conveying device 110 back to/into the fuel tank20. Here, the feed line (101) can be configured as a section of thereturn line 102, or vice versa. The water container 410 and/or the feedline 101 (preferably) have/has a water removal point 120, 420.

The water container 410 preferably has a water container sensor 430 orwater container detector 430 which outputs a sensor signal S1 in amanner which is dependent on a height or level of water 1 in the watercontainer 410. In the simplest case, the water container sensor 430 is athreshold value sensor. Via a sensor signal S1 (for example: “watercontainer full” (water container 410 which is filled sufficiently orsubstantially with water 1)), the preferably maintenance-free dewateringpump 110 conveys water 1 out of the water container 410 at the bottomdownward directly into the fuel tank 20. Deposited silt is swirled up inthe fuel 2 in the fuel tank 20 as a result of a return of the water 1into the fuel tank 20 at the bottom, and can be separated later in thefuel prefilter 40.

A valve (not shown), for example a check valve, in the return line 102can avoid an undesired return of water 1 out of the fuel tank 20 intothe water container 410. During discharging, said valve can be bypassedby way of the dewatering actuating means of the water removal point120/220/420. In addition to a sensor signal actuation, the dewateringpump 110 can also operate in an adjustably time-controlled or permanentmanner. A fuel 2 which is possibly entrained in all three cases does notlead to a failure. The water 1 can be discharged at the fuel tank 20(water removal point 220) and/or at the fuel prefilter 40 (water removalpoint 120, 420).

An operator or traction unit driver of the rail vehicle can continue ajourney safely and without an interruption until an upcoming fuel stop.Engine damage or even complete engine failure is avoided safely. Beforefilling of the rail vehicle, water 1 should be discharged at the fuelprefilter 40. The end criteria of this operation remain identical forthe operator or traction unit driver. Should no water 1 be discharged, afilling quantity of fuel 2 and therefore merely a range of the railvehicle are decreased.

FIG. 2 shows the second embodiment of the dewatering device 10. Here,the dewatering line 100 comprises a feed line 101 and merely a forwardfeed line 103. The feed line 101 leads from the water container 410 tothe water conveying device 110/into the forward feed line 103. Theforward feed line 103 leads from the feed line 101/from the waterconveying device 110 forward to/into the exhaust gas system 80, inparticular to/into the exhaust gas silencer 80. Here, the feed line(101) can be configured as a section of the forward feed line 103, orvice versa. The water container 410 (preferably) and/or the feed line101 have/has a water removal point 120, 420.

Here, as is also the case in FIG. 1, the water container sensor 430 orwater container detector 430 can be provided in an analogous manner.Furthermore, the exhaust gas system 80 or the exhaust gas silencer 80has a volumetric flow sensor 830 or volumetric flow detector 830. Here,the volumetric flow sensor 830 detects at least one volumetric flowthreshold value in at least one section of the exhaust gas system 80 orthe exhaust gas silencer 80, and generates a sensor signal S2.

Via a sensor signal S1 (for example, “water container full” (watercontainer 410 which is filled sufficiently or substantially with water1)) and the sensor signal S2 (for example, “volumetric flow reached”),the dewatering pump 110 conveys water 1 at the bottom out of the watercontainer 410, preferably assisted by way of a vacuum pump (opening ofthe forward feed line 103 on/in the exhaust gas system 80 or the exhaustgas silencer 80), into the exhaust gas system 80 or the exhaust gassilencer 80. Possibly present diesel particulates are burned in theexhaust gas silencer 80. The operator or traction unit driver no longerhas to discharge water 1 manually from the fuel prefilter 40 duringoperation of the rail vehicle. The rail vehicle is dewateredautomatically during operation. Engine damage or even complete enginefailure is avoided safely.

FIG. 3 shows the third embodiment of the dewatering device 10 which is acombination of the first and the second embodiment. That is to say, inaddition to the feed line 101, the dewatering line 100 has both thereturn line 102 and the forward feed line 103. Here, an actuating means106, in particular a valve 106, is preferably provided on/in thedewatering line 100, preferably between the feed line 101, the returnline 102 and the forward feed line 103. The path (water container 410 tothe fuel tank 20, water container 410 to the exhaust gas system 80, orfuel tank 20 to the exhaust gas system 80) which the separated water 1is to take can be set by means of the valve 106.

Furthermore, in exemplary embodiments, a volumetric flow through thereturn line 102 or the forward feed line 103 can be set by means of thevalve 106. Here, the water conveying device 110 is preferably coupledfluid-mechanically into/onto the feed line 101.

Via a sensor signal S1 (for example, “water container full” (watercontainer 410 which is filled sufficiently or substantially with water1)), the preferably maintenance-free dewatering pump 110 conveys water 1at the bottom out of the water container 410 downward directly into thefuel tank 20. A valve in the return line 102 prevents the undesiredreturn of the water into the fuel prefilter 40. During discharging, saidvalve can be bypassed by way of the dewatering actuating means of thewater removal point 120/220/420. The dewatering pump 110 can operate ina sensor-controlled, adjustably time-controlled or else permanentmanner. Entrained fuel 2 does not lead to a failure.

In addition, via the valve 106 (in the case of a currentless valve 106,a line 101/102 to the fuel tank 20 is preferably open or all lines 101,102, 103 are sealed with respect to one another), a conveying path canbe switched over to the exhaust gas system 80 or the exhaust gassilencer 80 if a sensor signal S2 (for example, “volumetric flowreached”) is present. Water 1 can preferably be discharged both at thefuel tank 20 and at the fuel prefilter 40. An operator or traction unitdriver of the rail vehicle can continue a journey safely and without aninterruption before an upcoming fuel stop, and can park the vehicle witha running engine at idling speed. The rail vehicle removes the waterfrom the fuel 2 during the journey. Engine damage or even completeengine failure is avoided safely.

1-15 (canceled)
 16. A method for dewatering a fuel during operation of arail vehicle, the method comprising the following steps: conveying fuelas an operating substance out of an operating substance tank; separatingwater present in the operating substance into a water container;conveying the water back into the operating substance tank if the watercontainer is substantially filled; and conveying the water out of thewater container into an exhaust gas system if an exhaust gas volumetricflow is at least sufficient and if the water container is substantiallyfilled, evaporating the water conveyed into the exhaust gas system in ahot exhaust gas flow and discharging the hot exhaust gas flow into alocal surrounding area.
 17. The dewatering method according to claim 16,which further comprises: using a water conveying device locatedsubstantially at a bottom of the water container to convey the waterinto the operating substance tank; and using the water conveying deviceto convey the water into the exhaust gas system.
 18. The dewateringmethod according to claim 16, which further comprises at least one of:discharging the water out of at least one of the operating substancetank or the water container; or conveying the operating substance out ofthe operating substance tank substantially at a height of a level of theoperating substance in the operating substance tank.
 19. The dewateringmethod according to claim 16, which further comprises temporallydischarging water present in an operating substance supply device of anengine before filling or starting up the engine.
 20. The dewateringmethod according to claim 16, which further comprises: conveying theoperating substance toward an internal combustion engine; using a waterconveying device configured as a dewatering pump to convey the water outof the water container; and operating the water conveying device in amanner controlled by a sensor signal, in an adjustable time-controlledmanner or permanently.
 21. A dewatering device for dewatering a fuelduring operation of a rail vehicle, the dewatering device comprising: anoperating substance tank for receiving fuel as an operating substance tobe conveyed out of said operating substance tank; a water container forseparating water present in the operating substance; an exhaust gassystem for evaporating water conveyed into said exhaust gas system in ahot exhaust gas flow and discharging the hot exhaust gas flow into alocal surrounding area; a dewatering line leading from said watercontainer to said operating substance tank and to said exhaust gassystem; said dewatering line conveying the water back into saidoperating substance tank if said water container is substantiallyfilled; and said dewatering line conveying the water out of said watercontainer into said exhaust gas system if an exhaust gas volumetric flowis at least sufficient and if said water container is substantiallyfilled.
 22. The dewatering device according to claim 21, which furthercomprises a water conveying device, said dewatering line including afeed line leading to said water conveying device, a return line leadingfrom said water conveying device to said operating substance tank and aforward feed line leading from said water conveying device to saidexhaust gas system.
 23. The dewatering device according to claim 21,wherein at least one of said water container, said operating substancetank, said dewatering line or said water conveying device has a waterremoval point.
 24. The dewatering device according to claim 22, wherein:the operating substance is discharged from said operating substancetank; said water container is part of an operating substance filter; andat least one of said feed line, said return line or said forward feedline has an actuating device.
 25. The dewatering device according toclaim 21, which further comprises: an operating substance intake floatconfigured to float on the operating substance in said operatingsubstance tank; and an operating substance hose disposed in saidoperating substance tank; said operating substance intake float and saidoperating substance hose being configured to convey the operatingsubstance out of said operating substance tank.